v2.0.0

Upgraded to groan_rs version 0.9

BREAKING CHANGES

• The short flag for specifying a structure file has been changed from -c to -s for consistency with Gromacs programs.
• The short flag for specifying a 'step' has consequently been changed from -s to -t.
• The keyword atomid is no longer supported, as per GSL v0.9.

New Features

• Added support for reading and writing trajectories in the gro format.
• Added support for reading and writing pqr structure files.

Bug Fixes

• The --whole flag now works for water molecules with SETTLE bonds.
• Regex operators can now be used inside regular expression blocks.